Oil-mist vaporizer attachment for engine carburetors



Jan. 6. 1925. 1,521,690

c. J. LAW

OIL MIST VAPORIZER ATTACHMENT FOR ENGINE CARBURETORS Filed July 24. 1923 Inveniof C J. L 37 b v- Patented Jan. 6, 1925.

UNITED STATES CLARENCE JOHN LAW, OF BALMAIN, NEAR ASSIGNOR TO ALBERT HER-BERT THOMPSON, OF

AUSTRALIA.

SYDNEY. NEW

SOUTH WALES, AUSTRALIA, SYDNEY, NEW SOUTH VAL-ES,

OIL-MIST VAPORIZER .ATTACHIVIEIIT FOR ENGINE OARBURETORS.

Application filed July 2 1923.

To all whom it may concern:

Be it known that I, CLAREN on JOHN LAW, subject of the King of Great Britain, residing at 103 Rowntree Street, Balmain, near Sydney, New South lVales, Australia, have invented certain new and useful Improvements in Oil-Mist Vaporizer Attachments for Engine Carburetors, of which the it'ollovying is a specification.

This invention relates to apparatus for heating fuel gas mixtures between a carburetor and the gas inlet passage of an internal combustion engine. tubular fitting in which during the starting of the engine the mixture is heated by electrical means and during running is heated by means of engine exhaust gases. The novelty consists in constructing the heater fitting with its interior surfaces electrically non-conductive, and winding and lacing a bare electrical conductor wire over said surtaces, said wire being terminally connected to a storage battery through a switch which controls a starting motor associated with the engine.

In the accompanying drawings,--

Fig. l is an elevat-ional'view with a portion in fragmentary section showing a hot box in the exhaust line of an engine, said box having alternative exhaust pipe connection sockets;

Fig. 2 is a transverse section on the line 2-2 Fig. 1;

Fig. 3 is an end elevational view of the tubular fitting in the hot box showing the heater coil winding; and

Fig. 4 is a diagrammatic view explanatory of the electrical heater circuit.

10 is a hot box which is introduced into the exhaust line of the engine by connections at opposite sides of it. For the purposes of illustration, alternative exhaust pipe connections 1112 are shown, the direction of flow of the hot exhaustgases being indicated by an arrow if the. exhaust gas enters through the pipe 8 and passes away through the pipe 12. In the normal arrangement the exhaust gas enters through the pipe 8 and passes away through the socket connection 9, the sockets at 11 and 12 being then plugged; the unused sockets are plugged whatever the pipe arrangement may be.

13 is a valve in the exhaust circuit, 14 a It consists in a Serial No: 653,559.

lever on the alve spindle, and 15 a connection to any appropriate control device within reach of the drivers hand. When the valve 13 is fitted, the hot circuit to the box 10 should be a bypass. from the main exhaust pipe from the engine. The tunetion of the valve 13 to control the temerature oi the heater device during the running of the engine, the engine driver being enabled, by means oi the control, to vary the temperature ot the induction gas according to his judgment. I

16 indicates the outer wall of an engine manifold. The hot box 10 has a central orifice formed through it in alignment with the manifold intake aperture 1'7. An open cylinder 18 is titted into this central orifice in the hot box 10, the fitting being facilitated by an end flange 19 on the cylinder which is spigoted into one wall of the hot box 10, a tight closure being made-by a gasket 2!) against the engine wall 16, and a joint with the uptake pipe 21 from the carburetor being completed by a gasket 22,, said gaskets 20 and 22 covering the joints. The cylinder 18 is crossed by two flat narrow tubes 23-24 extending through its walls. Exhaust gas in the box 10 circulates over the walls of the cylinder 18 and through the cross tubes 2324:. 25 is an inwardly disposed flange at that end of the cylinder 18 which is nearest the engine wall. The flange 25 is pierced symmetrically with holes 26. Interiorly the cylinder 18 is surfaced on its interior aspect with electrically insulating fire enamel; this enamel covers not only the interior surface of the cylinder 18, but also the outer surfaces of the flat cross tubes 2324; and the flange 25. and itlines the holes 26 in the flange 25. i

The electrical heater unit, consisting of a bare wire of nickel-chrome alloy 27, is wound helically around the flat cross tubes 2324 and is reeved to and fro through the holes 26 in the flange 25 to form a wire grid across the engine induction aperture 17. The cross section of the nickel-chrome wire 27 is proportioned according to its length so that said wire will be brought to a high temperature by the current obtained from the storage cell 28, but so as not to bring it to glowing temperature whereby ignition of the fuel might be caused whilst it is passing through the cylinder 18. The

ends of the wire 27 are brought out through a protective sheath 29 of asbestos, this sheath being detachably fixed in a stufiing box fitting 30 in the side of the uptake pipe 21 from the carburetor. One terminal of the wire 27 is connected to the battery lead 31 and the other terminal of it to the battery lead 32. These leads are branched in parallel with the starting motor 33, so that current flows through the wire 27 only whilst the starting motor is held in operation by the closing of the starter switch 34.

hen starting up an engine in cold condition, as soon as the starter switch 34: is closed current from the battery 28 flows through the heater wire 27, so that the wet gas which is delivered from the carburetor is preheated in passing over the hot wires 27; easy start'mg is thus facilitated. Iniinediaztely the engine starts up, the switch M is thrown out, and current is no longer taken through the wire 27; there-after heat derived from exhaust gases passing through the chamber 10 is utilized to heat the walls of the cylinder 18 and the cross tubes Iii-24, the driver controlling the temperature of the induction mixture during running by adjusting the valve 13 The device therefore functions automatically, co-acting with the starter motor to ensure warming up of all gas drawn into the engine, and cutting out the electrical heating element, and utilizing heat from exhaust gases immediately the engine is started, and during running of the engine.

Instead of constructing the cylinder 18 and its integral cross tubes 2324 of metal fire enainelled on the interior aspect to ensure electrical insulation where it is touched by the bare wires which form the electrical heater unit, the cylinder and its cross tubes may be constructed of porcelain; in this case it is desirable to form the flange 23 is a. separate ring inset into a spigoted end in the cylinder 18, but it is undesirable to use porcelain for the purpose, in view of the risk of cracking it in bolting up the heater and carluu-etor to the engine structure.

What I claim as my invention and desire to secure by Letters Patent is:-

A gas fuel mixture heater comprising a metal casing adapted to be titted in the exhaust gas pipe lineof an engine, a metal cylinder in the gas induction line, flat narrow tubes crossing said cylinder and terminally open to said casing, a coating of electrically insulating fire enamel upon the whole interior asi iect of said casing and the whole exterior aspect of said tubes, and an electrical resistance heater winding of bare wire wound over said tubes.

In testimony whereof I affix my signature.

CLARENCE JOHN LUV. 

